Note the line marked WORKAROUND, which fixes an
obscure error when starting a mod_perl-enabled Apache, by setting the
real UID to the effective UID. Without this workaround, a mismatch
between the real and the effective UIDs causes Perl to croak on the
-e switch.

This script depends on using a version of Perl that recognizes and
emulates the setuid bits. This script will do different things
depending on whether it is named start_httpd,
stop_httpd, or
restart_httpd; use symbolic links to create the
names in the filesystem.